• Cobalt-55;
  • Cobalt-58m;
  • radionuclide therapy;
  • Auger electrons;
  • PET

The SPECT compound 57Co-DOTATOC has recently been shown to have the highest affinity ever found for somatostatin receptor subtype 2. Moreover, the internalization rate into the tumour cell line AR42J was also the highest found for any somatostatin-based radiopharmaceutical. We here present a method to prepare the positron emission tomography compound 55Co-DOTATOC as a new promising radiopharmaceutical for positron emission tomography via solid target irradiations of enriched Fe-metal. Also, the new, potent Auger-electron-emitting radioisotope 58mCo and the resulting therapeutic compound 58mCo-DOTATOC as candidate for targeted radionuclide therapy of somatostatin receptor-positive tumours have been prepared with high yield and high radiochemical purity. Copyright © 2011 John Wiley & Sons, Ltd.